Free Email Deliverability Tools

Generate and validate SPF, DKIM and DMARC records, look up DNS, check deliverability, and more. All tools are free and require no account.

Email Authentication

SPF / DKIM / DMARC Checker

Run a full authentication check for your domain in seconds. See SPF, DKIM and DMARC status plus common misconfigurations.

plagiarism Open checker

SPF Record Generator

Build a valid SPF TXT record with includes, IP ranges and the right all policy. Copy and paste into your DNS provider.

tune Open SPF generator

SPF Record Lookup

Look up and validate the SPF record for any domain. Count DNS lookups, check enforcement, and spot permerror risk.

find_in_page Open SPF lookup

DMARC Record Generator

Generate a DMARC TXT record with p=none, quarantine or reject, plus RUA/RUF report addresses.

policy Open DMARC generator

DMARC Analyzer

Fetch and explain your DMARC record in plain language. Covers policy, alignment, rua/ruf, and common mistakes.

query_stats Open DMARC analyzer

DKIM Checker

Check if your DKIM selector is published correctly in DNS. Useful for Google Workspace, Microsoft 365, SendGrid, and more.

verified Open DKIM checker

DKIM Record Generator

Generate a DKIM key pair and DNS TXT record. Works with Postfix, cPanel, Google Workspace, Microsoft 365, and any mail server.

key Open DKIM generator

Email Header Analyzer

Paste raw email headers and extract SPF, DKIM and DMARC authentication results to see exactly why mail landed in spam.

mark_email_read Open header analyzer

DKIM Selector Finder

Automatically find active DKIM selectors for any domain by scanning 25+ common names. Works without knowing the selector in advance.

key_visualizer Find DKIM selectors

DNS Lookups

MX Lookup

Check MX records for any domain. Diagnose mail routing issues, verify provider setup, and confirm email hosting is configured.

alternate_email Open MX lookup

DNS TXT Lookup

List all TXT records for a domain. Great for checking SPF, DMARC, domain verification strings, and debugging conflicts.

list_alt Open TXT lookup

A Record Lookup

Look up IPv4 (A) and IPv6 (AAAA) records for any domain. Verify server IPs after a migration and confirm DNS changes propagated.

travel_explore Open A Record lookup

CNAME Lookup

Check CNAME records for any subdomain. Verify DKIM CNAME setup (Microsoft 365, SendGrid, Mailchimp) and custom sending domain aliases.

swap_horiz Open CNAME lookup

NS Lookup

Find the authoritative nameservers for any domain. Verify DNS delegation and confirm nameserver changes took effect.

dns Open NS lookup

Reverse DNS Lookup

Check the PTR record for any IP address. Diagnose missing or mismatched reverse DNS that causes mail servers to reject your email.

manage_search Open reverse DNS lookup

DNS Propagation Checker

Verify that a DNS record change has propagated by querying Google DNS and Cloudflare DNS directly. Works for SPF, DMARC, MX, A, and NS records.

sync Open propagation checker

SMTP Port Checker

Test whether ports 25, 587, and 465 are open and reachable on a mail server. Diagnose delivery failures when DNS looks correct.

electrical_services Check SMTP ports

SOA Record Lookup

Look up the Start of Authority record for any domain. See primary nameserver, serial number, refresh, retry, expire, and minimum TTL.

account_balance Open SOA lookup

WHOIS Lookup

Look up domain registration details: registrar, registration date, expiry date, nameservers, and domain status.

info Open WHOIS lookup

SPF Tester

Test whether a specific IP address is authorized to send email for your domain. See which mechanism matched and the PASS, SOFTFAIL, or FAIL verdict.

policy Test SPF

DMARC Policy Tester

Enter the From domain, SPF result, and DKIM result to see whether a message would pass or fail DMARC and what policy action applies.

shield Test DMARC

Reputation & Security

Blacklist Checker

Check if your domain or sending IP is listed on Spamhaus, SpamCop or Barracuda. Instant DNS blacklist results, no signup needed.

block Open blacklist checker

Email Address Validator

Check whether an email address has valid syntax and whether its domain has MX records. No test email sent, no bouncing required.

contact_mail Open email validator

BIMI Checker

Check if your domain has a BIMI record and whether your logo will display in Gmail, Apple Mail, and Yahoo.

image_search Open BIMI checker

MTA-STS Checker

Check if your domain has MTA-STS configured to force TLS on inbound email. Validates the DNS record and policy file.

lock Open MTA-STS checker

TLS-RPT Checker

Check if your domain has a TLS-RPT record to receive reports about TLS failures during email delivery. Checks for MTA-STS alongside it.

security Open TLS-RPT checker

Email Bounce Code Lookup

Paste any SMTP error code like 550, 421, or 554 5.7.26 and get a plain English explanation, common causes, and what to do.

help Look up bounce code

IP Address Info

Look up geolocation, ISP, ASN, and reverse DNS for any IP address. Identify mail server infrastructure and diagnose IP reputation issues.

location_on Look up IP

Email Header Security Analyzer

Paste raw email headers to analyze SPF, DKIM, DMARC, and ARC results. See the full received hop chain and identify authentication failures.

security Analyze headers

InboxGreen

FixKit Generator

Get copy-paste DNS fix records for your domain's email authentication issues, formatted for your specific DNS provider.

construction Open FixKit

Deliverability Badges

Copy-paste SVG badges that show your deliverability status on your website, linking back to a live InboxGreen check.

badge Get badges

InboxGreen API

Integrate SPF, DKIM and DMARC checks into your own workflows and dashboards using the InboxGreen API.

api View API docs

More tools coming soon. This page is the central hub for free email deliverability tools.